System for firing explosives in mines.



C. E. KNOWLES & L. D. CORNELIUS. SYSTEM FOR VFIRING EXPLOSIVES IN MINES. APPLICATION FILED DEC- 7, m4. RENEWED Jun-19.1916.

Patented Jan. 9, 1917. H E E E5 3 3m Swa 53 4 4 z rixiiufi 11m jfi 16$ 53% i L A 7 3 H E Emu" mm 4 6 2 Z E w x f a H 1 m 7 0 2 4 mm iii CQLL fiiu" Inventor.

O t t A Witnesses UNITED STATES PATENT oEEIoE.

CAMDEN EUGENE KNOWLES AND LEROY DANIEL CORNELIUS, OF PITTSBURG, KANSAS.

SYSTEM FOR FIRING EXPLOSIVES IN MINES.

Specification of Letters Patent.

Patented Jan. 9, 1917.

Application filed December 7, 1914, Serial No. 875,902. Renewed June 9, 1916. Serial No. 102,794.

To all whom it may concern Be it known that we, CAMDEN EUGENE KNowLEs and LEROY DANIEL CORNELIUS, citizens of the United States, residing at Pittsburg, in the county of Crawford, State of Kansas, have invented a new and useful. System for Firing Explosives in Mines, of which the following is a specification.

The present invention appertains to a system for firing explosives in mines, and

aims to provide a novel and improved system or apparatus adapted particularly for use in coal mines, whereby the explosives in the mine may be conveniently and effectively fired.

As a more specific object, this invention aims to provide a system of such a character that the agencies of air or other fluid under pressure may be utilized for operating circuit closers, to thereby establish electrical circuits within the various portions of the mine to bring the electrical squibs into action for firing the explosives.

Another object of the invention is to provide means in the system, whereby the various sets of circuit closers may be brought into action in a prearranged or predetermined order, so that the explosive in the various portions or branches of the mine may be set oil in a' given order.

It is also within the scope of the inven tion, to provide a system of the nature indicated, which will be comparatively simple and non-encumberin g in construction, which will be economical in application and maintenance, which will be safe, and which will possess dependability or reliability of action.

WVith the foregoing and other objects in view which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed can be made within the scope of what is claimed without departing from the spirit of the invention.

The invention is illustrated in its' preferred embodiment in the accompanying drawing, wherein:

Figure 1 is a diagrammatical illustration of the improved system. Fig. 2 is an enlarged sectional view taken through one of the circuit closers and attendant or accompanying parts. Fig. 3 is an enlarged sectional view through one of the pressure valves.

In carrying out the invention there is provided a main air or fluid conduit or pipe 1 extending into the mine, and having one end leading to and connected with 'an air or fluid tank 2 preferably disposed exteriorly of the mine at a suitable outlying point. A plurality of branches or laterals 3 are connected to and extend from the main conduit or pipe 1, and the branches or lateral pipes 3 extend 'into the various branches or portions of themine. The main conduit or pipe 1 is preferably provided with a controlling valve 4 adjacent the tank 2, and with an exhaust or outlet valve 5 beyond the valve 4, the valve 1 being operable to control the flow of air or pressure fluid from the tank 2 into the conduit or pipe 1, the valve 5 being operable to permit the compressed air or pressure fluid to discharge from the conduit or pipe 1 to the atmosphere.

Each of the branches 3 of the main conduit or pipe 1, is provided with or has interposed therein a valve structure or mechanism 6 embodying a suitable casing 7 attached to the sections of the branch 3, and having a partition 8 therein provided with openings 9 and 10 surrounded by oppositely facing valve seats 11 and 12, respectively; A valve 13 is operable with the seat 11 and is arranged to seat against the pressure of the air or fluid within the conduit or pipe 1, or

in other words, the valve 13 is seatable by a movement toward the conduit or pipe 1, considering the direction of flow of air or fluid from the conduit 1 into and through the branches. The valve 13 is provided with a tubular extension or socket 11, and a plug or cap 15 is secured through the casing 7 and is provided with a stem or finger 16 upon which-the tubular extension or socket 14 of the valve 13 is slidable snugly to guide the valve 13 to and from the seat 11. A coiled wire expansion spring 17. of graduated tension is positioned within the extension 14 of the valve'13 between the valve and stem or finger 16 and serves to yieldably seat the valve 13 under normal conditions. Each of the valve structures 6 also includes a valve 18 seatable against the valve seat 12 within the casing 7, the valve 18 being seatable in the direction opposite to the direction in which the valve 13 is seatable. The valve 18 is provided with a stem or shank tit? 19 received snugly and slidably by a tubular extension 20 or a plug or cap 21 engaged through the valve casing 7, so that the valve 18 is guided for movement to and from the seat 12.

Each of the branches 3 is equipped with a set or series of upstanding nozzles 22, which carry and operate the circuit closers 23. Each of the circuit closers comprises an apertured graphite piston 24 secured upon the upper end of the respective nozzle 22, and a cylinder 25 mounted slidably upon the piston 24, the lower end of the cylinder 25 being open, and the upper or outer end thereof being closed, and being provided with a socket 26 receiving ablock of insulation 27. A switch member 28 in the term of a cap, is engaged over the block of insulation 27, so as to be insulated from the cylinder 25.

Each of the circuit closers 23 is preferably inelosed within a case or box 29 having the 2 engaged upwardly through its bottom.

1 electrical circuit is associated with and arranged to be operated by each or" the cirelectrical squibs 31. The conductors 30 ex tend to the case or box 29 and their respective ends are connected to binding posts 32 engaged to the bottom of the box or case 29, and suitable batteries 33 are disposed within the case or box 29 for establishing the electrical circuit at the opportune time, although it is to be understood that an electrical circuit may be established by a dynamo or other suitable source of electrical current.

in order that the circuit closer 23 may close the circuit through the conductors 30, an insulated shelf or look 34: is secured within the case 2.) above the circuit closer 23, and pair of binding posts are engaged through tac shelf or block 34, and have contact brushes or springs 36 secured to their lower ends and lying in the path of the switch. member 28, so that when the cylinder 25 is raised or pushed away from the nozzle 22, the switch member 28 in contacting with the ends of the brushes or springs 36 will close the circuit. The end of one conductor 30 is connected to one of the brushes or contacts 36 by means of a leader or conductor 37, and the end of the other conduct r 30 is connected to one terminal of the batteries 33, by a wire or conductor 38, and ti e other terminal of the batteries 33 is connected to the other brush or contact 36 by a wire or conductor 39.

is preferable to provide a manually operable switch 40 in one of each pair of con ductors 30 adjacent the case or box 29, in

order that the electrical circuit may be opened and left opened during such periods when the establishment of the electrical circuit through the conductors 30 is not desired.

The branches or lateral pipes 3 are preterably grounded at intervals, as at 41, to eliminate stray or foreign circuit through the metallic conduits or pipes, and to thereby avoid any cross circuits or the like, which would be liable to prematurely or accidentally bring the squibs into action. The con doctors of the electrical circuits are also insulated thoroughly to enhance the safety of the present system.

A. coal mine may be readily and economically equipped with the present apparatus, the conduits or pipes 1 and 3 being readily and inexpensively applied therein, and it being noted that the electrical circuits are of short length of extent, and are isolated from their neighboring circuits, so as not to intertere with one another. In this manner, the use of trunk lines from the various firing circuits to an outlying generating station are eliminated, as has heretofore been the cause of a considerable outlay in equipping mines with the all electric systems, and such systems have not only been expensive to install and maintain, but have also been subjected to the dangers of sneak circuits shunts, cross circiuts and the hire, rendering the systems unreliable. The springs 17 of the various pressure valves 13 are of graduated tension, so that they will possess different degrees of strength, and in this manner the valve 13 having the weakest spring will be opened first under the pressure of air or fluid within the conduit or pipe 1, and the respective valves 13 will be opened in sequence or regular order according to the arrangement of the springs 17.

When it is desired to fire the explosives within the mine, the compressed air or pressure fluid within the tank is admitted into the main conduit or pipe 1 by opening the valve 4, and as the pressure rises Within the pipe 1, the valves 13 of the respective branches 3 will be opened in succession, and as soon as each of the valves 13 is forced open due to the fact that the compressed air overcomes the tension of the respective springs 17, the air will rush into the respective branches 3 and nozzles 22 thereof, so as to raise the pistons 25 and cause the switch members 28 carried thereby to close the respective electrical circuits, and whereupon the electrical squibs 31 will beset off for firing the explosives in the immediate vicinity of the mine. Thus, as the pressure of the air or fluid within the pipe or conduit 1 rises, the various sets or series of circuit closers will be operated in a regular or given order, and according to the time required to raise the pressure within the pipe or conduit 1.

After all of the shots have been fired, the operator or attendant opens the main conduit or pipe 1 to the atmosphere, by opening the valve 5, which will enable air and gases from the pneumatic system to be discharged into the atmosphere, the valves 18 which are ordinarily seated by the compressed air, being opened by the backward flow of the air or gas to permit the gas to flow from the branches 3 into the conduit or pipe 1 and thence into the atmosphere by way of the valve 5.

So soon as the air or fluid is exhausted suflieiently from the piping, all of the cylinders 25 of the circuit closers will descend by gravity and release all of the switch members 28 from the contacts 36, to thereby open all of the circuits. As a means for further precaution against accidents, the switches 40 at the heads of the firing circuits, may be opened at such times when it is not desirable for an electrical current to be set up in the circuits.

The present system in embodying the pneumatic apparatus for operating the circuit closers, eliminates the use of expensive electrical trunks, and furthermore enables the various circuits to be readily and timely closed.

The present system is operated when all of the miners are out of the mine, and there is no danger or risk incurred to life and limb. The shot firer may readily operate the system without subjecting himself to injury, and the present system is of advantage for other reasons which will be apparent to those versed in the art.

What is claimed is 1. A system for firing explosives in mines, comprising a fluid conduit extending into the mine, a normally open electrical circuit in the mine and including an electrical squib, and a fluid operated circuit closer for the said circuit and o )eratively connected to the said conduit.

2. In a system for firing explosives in mines, a fluid conduit extending into the mine, a plurality of fluid operated circuit closers operatively connected thereto, :1 normally open electrical circuit in the mine cooper-able with each circuit closer and arranged to be closed thereby, said circuits including electrical squibs and means for rendering the various circuit closers inoperative until various predetermined pressures of the fluid are attained.

3. A system for firing explosives in mines, comprising a fluid conduit extending into the mine and having a. plurality of branches extending into the branches of the mine, each branch having a valve for controlling the passage of fluid from the conduit thereinto, means for holding the respective valves closed until the pressure of the fluid Within the conduit rises to predetermined degrees, a fluid operated circuit closer operatively connected to each branch, and a normally open electrical circuit associated with each circuit closer and arranged to be closed thereby, said circuits including electrical squibs.

4:. A system for firing explosives in a mine, comprising a fluid conduit extending into the mine and having a plurality of branches extending into the branches of the mine, each branch having a valve for controlling the passage from the conduit thereinto and a check valve for allowing the fluid to flow back from the branch into the conduit, means for holding the respective first mentioned valves closed until the pressure of the fluid within the conduit rises to predetermined degrees, a fluid operated circuit closer operatively connected to each branch, and a normally open electrical circuit associated with each circuit closer and arranged to be closed thereby, said circuits including electrical squibs.

5. A system for firing explosives in a mine, comprising a fluid conduit extending into the mine and having a nozzle, a cylinder slidable upon said nozzle to be moved thereon by the action of the fluid in the conduit, an electrical circuit in the mine including an electrical squib and a pair of con tacts, and an insulated switch'member carried by said cylinder and cooperable with said contacts to close said circuit when the cylinder is moved by the action of the fluid. In testimony that we claim the foregoing as our own, we have hereto afiixed our signatures in the presence of two witnesses. CAMDEN EUGENE KNOWLES. LEROY DANIEL CORNELIUS. Witnesses Crrns'rnn MAYNARD, M. PAULLIN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

